Control of web elongation

Claim 1

IN AN OPERATION OF THE TYPE WHEREIN A WEB OF FLEXIBLE MATERIAL CARRYING A PREAPPLIED REPETITIVE PATTERN OF WORK IS SUPPLIED FROM A ROLL THEREOF TO A LOCUS IN WHICH ANOTHER REPETITIVE PATTERN OF WORK IS APPLIED TO THE WEB IN PREDETERMINED AND SUBSTANTIALLY FIXED SPACE RELATION TO SAID PREAPPLIED PATTERN, AN APPARATUS INCLUDING MEANS FOR DETECTING DEVIATIONS FROM THE DESIRED PREDETERMINED SPACE RELATION AND DERIVING THEREFROM ELECTRICAL SIGNALS INDICATIVE OF THE DIRECTION AND EXTENT OF THE DEVIATIONS, AND AN IMPROVED MEANS OF EFFECTING RAPID CORRECTION OF THE DETECTED DEVIATIONS WHICH COMPRISES, IN COMBINATION: A WEB COMPENSATOR HAVING A PLURALITY OF TUBULAR MEMBERS SPANNING THE WEB WIDTH AND DISPOSED IN SPACED RELATION TO EACH OTHER AND IN CONTACT WITH THE WEB AT A LOCATION BETWEEN SAID ROLL AND SAID LOCUS, MEANS CONNECTED WITH AT LEAST ONE OF SAID TUBULAR MEMBERS FOR CHANGING THEIR RELATIVE POSITIONS IN A MANNER WHEREBY ANY SUCH CHANGE ALTERS BOTH THE LENGTH OF THE PATH OF WEB TRAVEL ABOUT SAID MEMBERS AND THEIR ARC OF CONTACT WITH THE WEB, MEANS CONNECTED WITH THE TUBULAR MEMBERS FOR RETAINING THEM AT ANY RELATIVE POSITION RESULTING FROM SUCH CHANGE REGARDLESS TO CHANGES IN WEB TENSION, AND MEANS RESPONSIVE TO THE ELECTRICAL SIGNALS DERIVED FROM SAID DETECTED DEVIATIONS FOR EFFECTING THE CHANGES REQUIRED IN THE RELATIVE POSITIONS OF SAID TUBULAR MEMBERS TO CORRECT THE DEVIATIONS, A MOMENTARY CORRECTION BEING OBTAINED BY THE RESULTING CHANGE IN THE LENGTH OF SAID WEB PATH AND A PERSISTENT CORRECTION, FOR DEVIATIONS WHICH WOULD OTHERWISE BE CUMULATIVE, BEING OBTAINED BY THE CHANGE IN SAID ARC OF CONTACT AND THE RESULTING CHANGE IN WEB TENSION.